Web API will not use ISerializable implementation - serialization

I thought I had jumped through the necessary hoops to get my JsonMediaTypeFormatter working with custom ISerializable implementations, complete with passing unit tests. But I'm unable to get it to work when I pass in values via Swagger UI.
My key questions are:
What am I doing wrong with my unit test causing it to serialize/deserialize different from what Web API is doing?
What do I need to change to get this working with Web API's serializing/deserialization and Swagger/Swashbuckle?
Class being serialized: (Notice that serializing and then deserializing drops off the time component and only keeps the date component. The helps for testing/observing purposes.)
public class Pet : ISerializable
{
public DateTime Dob { get; set; }
public Pet()
{
Dob = DateTime.Parse("1500-12-25 07:59:59");
}
public Pet(SerializationInfo info, StreamingContext context)
{
Dob = DateTime.Parse(info.GetString("Dob"));
}
public void GetObjectData(SerializationInfo info, StreamingContext context)
{
info.AddValue("Dob", Dob.Date.ToString());
}
}
Web API Method: (always returns null)
public class TestController : ApiController
{
[Route("~/api/Pet")]
public string Get([FromUri] Pet data)
{
return data.Dob.ToString();
}
}
Passing Unit Test: (and serialization helpers from MSDN docs)
[TestFixture]
public class SerializationTests
{
[Test]
public void PetTest()
{
var date = new DateTime(2017, 1, 20, 5, 0, 0);
var foo = new Pet { Dob = date };
var jsonFormatter = new JsonMediaTypeFormatter { SerializerSettings = new JsonSerializerSettings { ContractResolver = new DefaultContractResolver { IgnoreSerializableInterface = false } } };
var serialized = SerializationHelpers.Serialize(jsonFormatter, foo);
Console.WriteLine(serialized);
var deserialized = SerializationHelpers.Deserialize<Pet>(jsonFormatter, serialized);
Assert.That(foo.Dob, Is.Not.EqualTo(date.Date));
Assert.That(deserialized.Dob, Is.EqualTo(date.Date));
}
}
public static class SerializationHelpers
{
public static string Serialize<T>(MediaTypeFormatter formatter, T value)
{
// Create a dummy HTTP Content.
Stream stream = new MemoryStream();
var content = new StreamContent(stream);
// Serialize the object.
formatter.WriteToStreamAsync(typeof(T), value, stream, content, null).Wait();
// Read the serialized string.
stream.Position = 0;
return content.ReadAsStringAsync().Result;
}
public static T Deserialize<T>(MediaTypeFormatter formatter, string str) where T : class
{
// Write the serialized string to a memory stream.
Stream stream = new MemoryStream();
StreamWriter writer = new StreamWriter(stream);
writer.Write(str);
writer.Flush();
stream.Position = 0;
// Deserialize to an object of type T
return formatter.ReadFromStreamAsync(typeof(T), stream, null, null).Result as T;
}
}
WebApiConfig.cs
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// Web API configuration and services
config.Formatters.Clear();
var jsonFormatter = new JsonMediaTypeFormatter { SerializerSettings = new JsonSerializerSettings { ContractResolver = new DefaultContractResolver { IgnoreSerializableInterface = false } } };
config.Formatters.Add(jsonFormatter);
// Web API routes
config.MapHttpAttributeRoutes();
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
}
}
A few other notes:
When I run the passing unit test, the Console.WriteLine output is:
{"Dob":"1/20/2017 12:00:00 AM"}
which is exactly what I want/expect.
My Swagger UI looks like this using the default Swashbuckle settings from Nuget. Note that value of the date is what is set in the default constructor, showing that my ISerializable implementation is ignored.
NOTE:
I have changed the question to remove all generics from the picture. This problem is fundamentally about ISerializable implementations now and not about Generics.

WebAPI api does not know how to deserialize this generic object. I see a similar question here in SO but did not personally try/test it. Hope it helps: Generic Web Api method
Rather than having a generic method, you can create a generic controller. So your code above will look something like below.
public abstract class MyClass{ }
public class PersonDto: MyClass{}
public class TestController<T> : ApiController where T: MyClass
{
public string Get([FromUri] T data)
{
...
}
}

Related

How to write Xunit test case of factory design pattern code block which is tightly coupled?

I would like to write xunit test case of below method. Could you please suggest alternate design so i can write xunit test case with minimum change in my current project.
public ActionResult Index(int id = 0, AssetFilterType filter = AssetFilterType.All)
{
using (var tracer = new Tracer("AssetController", "Index"))
{
RemoveReturnUrl();
ViewBag.JobId = id;
var response = ContextFactory.Current.GetDomain<EmployeeDomain>().GetEmployeeFilterAsync(id,
CurrentUser.CompanyId, filter); // Not able write unit test case , please suggest alternate design.
return View("View", response);
}
}
current design is as follow
public interface IDomain
{
}
public interface IContext
{
D GetDomain<D>() where D : IDomain;
string ConnectionString { get; }
}
public class ApplicationContext : IContext
{
public D GetDomain<D>() where D : IDomain
{
return (D)Activator.CreateInstance(typeof(D));
}
public string ConnectionString
{
get
{
return "DatabaseConnection";
}
}
}
public class ContextFactory
{
private static IContext _context;
public static IContext Current
{
get
{
return _context;
}
}
public static void Register(IContext context)
{
_context = context;
}
}
//var response = ContextFactory.Current.GetDomain**< EmployeeDomain>**().GetEmployeeFilterAsync(id,
CompanyId, filter);
This line serve purpose to call specific class method i.e GetEmployeeFilterAsync from EmployeeDomain. Although it is very handy and widely used in our application but due to design issue i am not able to write unit
test case.
Could you please suggest design so with the minimum change we can write unit test case.
Don't use the Service Locator anti-pattern, use Constructor Injection instead. I can't tell what AssetDomain is from the OP, but it seems as though it's the dependency that matters. Inject it into the class:
public class ProbablySomeController
{
public ProbablySomeController(AssetDomain assetDomain)
{
AssetDomain = assetDomain;
}
public AssetDomain AssetDomain { get; }
public ActionResult Index(int id = 0, AssetFilterType filter = AssetFilterType.All)
{
using (var tracer = new Tracer("AssetController", "Index"))
{
RemoveReturnUrl();
ViewBag.JobId = id;
var response = AssetDomain.GetAssetFilterAsync(id, CurrentUser.CompanyId, filter);
return View("View", response);
}
}
}
Assuming that AssetDomain is a polymorphic type, you can now write a test and inject a Test Double:
[Fact]
public void MyTest()
{
var testDouble = new AssetDomainTestDouble();
var sut = new ProbablySomeController(testDouble);
var actual = sut.Index(42, AssetFilterType.All);
// Put assertions here
}
step1 : Required library
step 2 : When the application starts , register required domain like
protected void Application_Start()
UnityConfig.RegisterComponents();
Step 3: create one static class and register all your domain
example
public static class UnityConfig
{
public static void RegisterComponents()
{
var container = new UnityContainer();
Initialize domain which will injected in controller
container.RegisterType<IPricingDomain, PricingDomain>();
GlobalConfiguration.Configuration.DependencyResolver = new UnityDependencyResolver(container);
}
}
step 4 :
so you can inject respective interface in constructor
in controller file.
goal : get rid of below any pattern in your project.
and start writing unit test cases.

ASP.NET Core WebAPI XML Method argument deserialization

I'm trying to make a WebAPI controller on .NET Core 3.1 witch supports both JSON and XML as request/response content-type.
Controller works perfectly when it receive JSON with "application/json", but when it receive XML with "application/xml", method argument are created with default values, not values that was posted in request body.
Example project - https://github.com/rincew1nd/ASPNetCore_XMLMethods
Additional XML serializer in startup:
services.AddControllers().AddXmlSerializerFormatters();
Controller with method and test model:
[ApiController]
[Route("[controller]")]
public class TestController : ControllerBase
{
[HttpPost, Route("v1")]
[Consumes("application/json", "application/xml")]
[Produces("application/json", "application/xml")]
public TestRequest Test([FromBody] TestRequest data)
{
return data;
}
}
[DataContract]
public class TestRequest
{
[DataMember]
public Guid TestGuid { get; set; }
[DataMember]
public string TestString { get; set; }
}
P.S. Project contains Swagger for API testing purposes.
Your xml post request body uses camel cases which results in the model binding as null.
Add using Swashbuckle.AspNetCore.SwaggerGen; in starup.cs and try to configure like below code:
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers().AddXmlSerializerFormatters();
services.AddSwaggerGen(c =>
{
c.SwaggerDoc("v1", new OpenApiInfo { Title = "Neocase <-> 1C Integration", Version = "v1" });
c.SchemaFilter<XmlSchemaFilter>();
});
}
public class XmlSchemaFilter : Swashbuckle.AspNetCore.SwaggerGen.ISchemaFilter
{
public void Apply(OpenApiSchema model, SchemaFilterContext context)
{
if (model.Properties == null) return;
foreach (var entry in model.Properties)
{
var name = entry.Key;
entry.Value.Xml = new OpenApiXml
{
Name = name.Substring(0, 1).ToUpper() + name.Substring(1)
};
}
}
}
Don't use FromBody attribute for application/xml.
When a parameter has [FromBody], Web API uses the Content-Type header to select a formatter. In this example, the content type is "application/json" and the request body is a raw JSON string (not a JSON object).
Using [FromBody]
After some more research i found that swagger generates wrong xml examples without even noticing custom naming of classes or properties.
I wrote custom schema for naming xml attributes as they are named by XML attributes.
Only problem i faced is that SchemaFilterContext doesn't provide description of properties of Enum type. So to name Enums i use custom attribute for swagger name and XMLElementAttribute on property with same names (yeah, it's junky but works).
public class XmlSchemaFilter : ISchemaFilter
{
public void Apply(OpenApiSchema schema, SchemaFilterContext context)
{
//Try to find XmlRootAttribute on class
var xmlroot = context.Type.GetAttributeValue((XmlRootAttribute xra) => xra);
if (xmlroot != null)
{
schema.Xml = new OpenApiXml
{
Name = xmlroot.ElementName
};
}
//Try to find XmlElementAttribute on property
if (context.MemberInfo != null)
{
var xmlelement = context.MemberInfo.GetAttributeValue((XmlElementAttribute xea) => xea);
if (xmlelement != null)
{
schema.Xml = new OpenApiXml
{
Name = xmlelement.ElementName
};
}
}
//Try to find XmlEnumNameAttribute on enums
if (context.Type.IsEnum)
{
var enumname = context.Type.GetAttributeValue((XmlEnumNameAttribute xea) => xea);
if (enumname != null)
{
schema.Xml = new OpenApiXml
{
Name = enumname.ElementName
};
}
}
}
}
public static class AttributeHelper
{
public static TValue GetAttributeValue<TAttribute, TValue>(
this Type type,
Func<TAttribute, TValue> valueSelector)
where TAttribute : Attribute
{
var att = type.GetCustomAttributes(
typeof(TAttribute), true
).FirstOrDefault() as TAttribute;
if (att != null)
{
return valueSelector(att);
}
return default(TValue);
}
public static TValue GetAttributeValue<TAttribute, TValue>(
this MemberInfo mi,
Func<TAttribute, TValue> valueSelector)
where TAttribute : Attribute
{
var att = mi.GetCustomAttributes(
typeof(TAttribute), true
).FirstOrDefault() as TAttribute;
if (att != null)
{
return valueSelector(att);
}
return default(TValue);
}
}

Service fabric remoting serializer

In experimenting with Service Fabric remoting I have some data types that are not serialized correctly. This is causing me many issues.
From the documentation it appears that everything needs to be decorated with [DataContract]. After using this on some test types it does appear that they serialize correctly.
However I frankly don't want to have to decorate everything. That would be a huge step backwards for me. I would prefer to use custom serialization all the way around.
This documentation seems to suggest that it is possible to register a custom serializer however it appears to only be for stateful services. I am primarily using remoting with stateless services.
The current remoting stack requires that your types use DataContract. Supposedly the team is close to releasing a new remoting stack in the near future that contains the ability to plug in custom serialization and a lot of improvements on the performance side but this is not available yet.
In the meantime, a workaround (not a very nice one mind you) is to make all of your proxies receive string or byte[] or something like that and take care of serialization/deserialization manually using something like JSON.Net. Personally I'd bite the bullet and make your types Data Contract Serializable until the new remoting bits are available.
With the release of Service Fabric V2 Remoting, this is now possible. See here for further details. Below
Here is an implementation of MessagePack remoting serializer I have used, but in your case the JSON example in the docs would probably suffice.
public class MessagePackMessageFactory : IServiceRemotingMessageBodyFactory
{
public IServiceRemotingRequestMessageBody CreateRequest(string interfaceName, string methodName, int numberOfParameters)
{
return new MessagePackRemotingRequestMessageBody(numberOfParameters);
}
public IServiceRemotingResponseMessageBody CreateResponse(string interfaceName, string methodName)
{
return new MessagePackServiceRemotingResponseMessageBody();
}
}
[MessagePackObject]
public class MessagePackRemotingRequestMessageBody : IServiceRemotingRequestMessageBody
{
[Key(0)]
public object Value;
public MessagePackRemotingRequestMessageBody()
{
}
public MessagePackRemotingRequestMessageBody(int parameterInfos)
{
}
public void SetParameter(int position, string paramName, object parameter)
{
Value = parameter;
}
public object GetParameter(int position, string paramName, Type paramType)
{
return Value;
}
}
[MessagePackObject]
public class MessagePackServiceRemotingResponseMessageBody : IServiceRemotingResponseMessageBody
{
[Key(0)]
public object Response;
public object Get(Type paramType)
{
// ignore paramType?
return Response;
}
public void Set(object response)
{
Response = response;
}
}
public class ServiceRemotingResponseMessagePackMessageBodySerializer : IServiceRemotingResponseMessageBodySerializer
{
public OutgoingMessageBody Serialize(IServiceRemotingResponseMessageBody responseMessageBody)
{
if (!(responseMessageBody is MessagePackServiceRemotingResponseMessageBody body))
{
return new OutgoingMessageBody(new[] { new ArraySegment<byte>(new byte[0]) });
}
var bytes = MessagePackSerializer.Serialize(body, ServiceFabricResolver.Instance);
return new OutgoingMessageBody(new[] { new ArraySegment<byte>(bytes) });
}
public IServiceRemotingResponseMessageBody Deserialize(IncomingMessageBody messageBody)
{
using (var stream = messageBody.GetReceivedBuffer())
{
if (stream.Length == 0)
{
return new MessagePackServiceRemotingResponseMessageBody();
}
var body = MessagePackSerializer.Deserialize<MessagePackServiceRemotingResponseMessageBody>(stream, ServiceFabricResolver.Instance);
return body;
}
}
}
public class ServiceRemotingMessagePackSerializationProvider : IServiceRemotingMessageSerializationProvider
{
public IServiceRemotingRequestMessageBodySerializer CreateRequestMessageSerializer(Type serviceInterfaceType,
IEnumerable<Type> requestBodyTypes)
{
return new ServiceRemotingRequestMessagePackMessageBodySerializer();
}
public IServiceRemotingResponseMessageBodySerializer CreateResponseMessageSerializer(Type serviceInterfaceType, IEnumerable<Type> responseBodyTypes)
{
return new ServiceRemotingResponseMessagePackMessageBodySerializer();
}
public IServiceRemotingMessageBodyFactory CreateMessageBodyFactory()
{
return new MessagePackMessageFactory();
}
}
public class ServiceRemotingRequestMessagePackMessageBodySerializer : IServiceRemotingRequestMessageBodySerializer
{
public OutgoingMessageBody Serialize(IServiceRemotingRequestMessageBody serviceRemotingRequestMessageBody)
{
if (serviceRemotingRequestMessageBody == null) return null;
if (!(serviceRemotingRequestMessageBody is MessagePackRemotingRequestMessageBody body))
{
return new OutgoingMessageBody(new[] { new ArraySegment<byte>(new byte[0]) });
}
var bytes = MessagePackSerializer.Serialize(body, ServiceFabricResolver.Instance);
return new OutgoingMessageBody(new[] { new ArraySegment<byte>(bytes) });
}
public IServiceRemotingRequestMessageBody Deserialize(IncomingMessageBody messageBody)
{
using (var stream = messageBody.GetReceivedBuffer())
{
if (stream.Length == 0)
{
return new MessagePackRemotingRequestMessageBody();
}
var body = MessagePackSerializer.Deserialize<MessagePackRemotingRequestMessageBody>(stream, ServiceFabricResolver.Instance);
return body;
}
}
}

Serialising multiple return types with Request.CreateResponse

I have an action method for an API that returns an HttpResponseMessage, however based on the Accept header this can return many different formats of data.
This is what I have at the moment, which does work, but it's not very desirable, as I'll have to remember to include any new classes in the MappedItem method, and there will be lots.
[HttpGet]
public HttpResponseMessage Get(int id)
{
var result = _builder.Build(id);
return MappedItem(result);
}
protected HttpResponseMessage MappedItem<T>(T item)
{
// Maps the class to the media type defined in the Accept header
var destinationType = GetDestinationType();
var type = typeof(T);
var mapped = Mapper.Map(item, type, destinationType);
if (mapped is ApiModelV1) {
return Request.CreateResponse(HttpStatusCode.OK, mapped as ApiModelV1);
}
return Request.CreateResponse(HttpStatusCode.OK, mapped);
}
It works fine without the if (mapped is ApiModelV1) part if I'm just serialising to JSON, but throws an exception if I'm serialising to XML. Does anyone know a way of doing this in a more generic way?
One possibility is to decorate your base class with the KnownType attribute and list all possible derived classes to indicate to the XML serializer about the existence of those types:
[KnownType(typeof(ApiModelV1))]
[KnownType(typeof(ApiModelV2))]
public class BaseClass
{
...
}
Alternatively if you don't want to pollute your models with such attributes you could use a custom XML serializer and indicate the known types:
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
var knownTypes = new Type[]
{
typeof(ApiModelV1),
typeof(ApiModelV2),
};
config.Formatters.XmlFormatter.SetSerializer<BaseClass>(
new DataContractSerializer(typeof(BaseClass), knownTypes)
);
}
}
OK, I've found a solution, although I've had to resort to using reflection, as I couldn't get it working properly with known types.
protected HttpResponseMessage MappedItem<T>(T item)
{
var destinationType = GetDestinationType();
var type = typeof(T);
var mapped = Mapper.Map(item, type, destinationType);
MethodInfo method = this.GetType().GetMethod("CreateResponse", BindingFlags.Public | BindingFlags.Instance);
method = method.MakeGenericMethod(mapped.GetType());
return (HttpResponseMessage)method.Invoke(this, new[] {mapped});
}
public HttpResponseMessage CreateResponse<T>(T obj)
{
return Request.CreateResponse(HttpStatusCode.OK, obj);
}
It's not ideal, but it's far more favourable than having lots of if (mapped is ...) for every type that I want to serialise.

ASP.NET Web API OData Action on the EDM Model Root

I'm building a Web API service using OData, and would like to expose a method as an Action in the service as follows.
http://myServer/odata/myAction
I'm currently mapping the OData routes as follows:
Dim modelBuilder As ODataModelBuilder = New ODataConventionModelBuilder
modelBuilder.EntitySet(Of Product)("Products")
Dim myAction = modelBuilder.Action("myAction")
myAction.Parameter(Of String)("Parameter1")
myAction.Returns(Of Boolean)()
Dim model As IEdmModel = modelBuilder.GetEdmModel
config.Routes.MapODataRoute("ODataRoute", "odata", model)
This wonderful tutorial shows how to associate an action with an entity like this:
http://myServer/odata/Products(1)/myAction
Following the tutorial, I can then write the method for the action in the ProductsController class after creating the model with the following line:
Dim myAction = modelBuilder.Entity(Of Product).Action("myAction")
However, if I don't want to associate the action with an entity, where would I write the method for the action? Is there a DefaultController class I need to write?
We currently do not have support for this out of the box, but its very easy to do it yourself. Example below (This nice sample is actually from Mike Wasson which is yet to be made public :-))
------------------------------------------------------
// CreateMovie is a non-bindable action.
// You invoke it from the service root: ~/odata/CreateMovie
ActionConfiguration createMovie = modelBuilder.Action("CreateMovie");
createMovie.Parameter<string>("Title");
createMovie.ReturnsFromEntitySet<Movie>("Movies");
// Add a custom route convention for non-bindable actions.
// (Web API does not have a built-in routing convention for non-bindable actions.)
IList<IODataRoutingConvention> conventions = ODataRoutingConventions.CreateDefault();
conventions.Insert(0, new NonBindableActionRoutingConvention("NonBindableActions"));
// Map the OData route.
Microsoft.Data.Edm.IEdmModel model = modelBuilder.GetEdmModel();
config.Routes.MapODataRoute("ODataRoute", "odata", model, new DefaultODataPathHandler(), conventions);
--------------------------------------------------------------
// Implements a routing convention for non-bindable actions.
// The convention maps "MyAction" to Controller:MyAction() method, where the name of the controller
// is specified in the constructor.
public class NonBindableActionRoutingConvention : IODataRoutingConvention
{
private string _controllerName;
public NonBindableActionRoutingConvention(string controllerName)
{
_controllerName = controllerName;
}
// Route all non-bindable actions to a single controller.
public string SelectController(ODataPath odataPath, System.Net.Http.HttpRequestMessage request)
{
if (odataPath.PathTemplate == "~/action")
{
return _controllerName;
}
return null;
}
// Route the action to a method with the same name as the action.
public string SelectAction(ODataPath odataPath, System.Web.Http.Controllers.HttpControllerContext controllerContext, ILookup<string, System.Web.Http.Controllers.HttpActionDescriptor> actionMap)
{
if (controllerContext.Request.Method == HttpMethod.Post)
{
if (odataPath.PathTemplate == "~/action")
{
ActionPathSegment actionSegment = odataPath.Segments.First() as ActionPathSegment;
IEdmFunctionImport action = actionSegment.Action;
if (!action.IsBindable && actionMap.Contains(action.Name))
{
return action.Name;
}
}
}
return null;
}
}
--------------------------------------------------
// Controller for handling non-bindable actions.
[ODataFormatting]
[ApiExplorerSettings(IgnoreApi = true)]
public class NonBindableActionsController : ApiController
{
MoviesContext db = new MoviesContext();
[HttpPost]
public Movie CreateMovie(ODataActionParameters parameters)
{
if (!ModelState.IsValid)
{
throw new HttpResponseException(HttpStatusCode.BadRequest);
}
string title = parameters["Title"] as string;
Movie movie = new Movie()
{
Title = title
};
db.Movies.Add(movie);
db.SaveChanges();
return movie;
}
protected override void Dispose(bool disposing)
{
db.Dispose();
base.Dispose(disposing);
}
}